The new Food and Drug Administration (FDA) chief said he will prioritize fighting so-called “misinformation,” although he did not specify anything in particular. “A purely reactive mode is not appropriate, particularly in this new era of social media,” incoming FDA Commissioner Robert Califf, who was just recently a senior adviser at Google Health and Verily, told FDA staff in a letter that was made public this week. “These kinds of distortions and half-truths that find their way into the public domain do enormous harm, both by leading people to behavior that is detrimental to their health and by causing them to eschew interventions that would improve their health,” he added. Califf did not elaborate on what he considers misinformation. Also unclear is how the FDA will attempt to counter it online. Critics of COVID-19 rules have said that the term “misinformation,” often deployed in mainstream media outlets and by public officials, …